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1.
Artigo em Inglês | MEDLINE | ID: mdl-38213844

RESUMO

Natural compounds that have the potential to act as antimicrobials and antitumors are a constant search in the field of pharmacotherapy. Eragrostis plana NEES (Poaceae) is a grass with high allelopathic potential. Allelopathy is associated with compounds generated in the primary and secondary metabolism of the plant, which act to protect it from phytopathogens. Tabernaemontana catharinensis A DC (Apocynaceae), a tree in which its leaves and bark are used for the preparation of extracts and infusions that have anti-inflammatory and antinociceptive effects, is attributed to its phytochemical constitution. The objective of this study was to elucidate the phytochemical constitution, the antibacterial potential, the toxicity against immune system cells, hemolytic potential, and antitumor effect of methanolic extracts of E. plana and T. catharinensis. The phytochemical investigation was carried out using the UHPLC-QTOF MS equipment. The antibacterial activity was tested using the broth microdilution plate assay, against Gram-negative and Gram-positive strains, and cytotoxicity assays were performed on human peripheral blood mononuclear cells (PBMC) and in vitro hemolysis. Antitumor activity was performed against the colon cancer cell line (CT26). Results were expressed as mean and standard deviation and analyzed by ANOVA. p < 0.05 was considered significant. More than 19 possible phytochemical constituents were identified for each plant, with emphasis on phenolic compounds (acids: vanillic, caffeic, and quinic) and alkaloids (alstovenine, rhyncophylline, amezepine, voacangine, and coronaridine). Both extracts showed antibacterial activity at concentrations below 500 µg/mL and were able to decrease the viability of CT26 at concentrations below 2000 µg/mL, without showing cytotoxic effect on PBMCs and in vitro hemolysis at the highest concentration tested. This is the first report of the activity of E. plana and T. catharinensis extracts against colon cancer cell line (CT26). Studies should be carried out to verify possible molecular targets involved in the antitumor effect in vivo.

2.
Nat Prod Res ; 37(5): 764-768, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35617512

RESUMO

Richardia brasiliensis is a species used in folk medicine and rich in active compounds. In this study, the extracts were submitted to UHPLC-ESI-MS/MS analysis and total polyphenols, tannins, and flavonoids assays. Besides, it was determined its antioxidant capacity, oxidative stress markers and toxicological profile. Fourteen polyphenols were found and, in the dosages, a slight change in the concentrations in each extract was observed. Regarding the antioxidant capacity, the responses were different in the methods used. There was an increase in lipid peroxidation, and NO, however total ROS remained unchanged. The cells remained more than 90% viable and the extracts did not cause damage to single strands of DNA, with the exception of the crude autumn and spring extracts at 500 µg/mL. The results found in this study suggest that extracts are potentially toxic to human leukocyte cells in high concentrations; however, more studies should be performed in different cell lines.


Assuntos
Antioxidantes , Rubiaceae , Humanos , Antioxidantes/farmacologia , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Espectrometria de Massas em Tandem , Taninos , Polifenóis/farmacologia , Compostos Fitoquímicos/análise , Flavonoides/farmacologia , Flavonoides/análise
3.
Ars pharm ; 63(4): 320-334, oct.-dic. 2022. ilus, tab, graf
Artigo em Inglês | IBECS | ID: ibc-210488

RESUMO

Introducción: Momordica charantia L. es ampliamente utilizada para consumo y medicina tradicional debido a sus actividades biológicas. Sin embargo, se sabe poco sobre los efectos del melón amargo en las células sanas. Por lo tanto, nuestro objetivo fue evaluar los efectos del extracto de Momordica charantia en linfocitos humanos aislados, especialmente en aspectos inflamatorios, citotóxicos, genotóxicos y mutagénicos. Método : Para ello se preparó un extracto hidroetanólico con frutos y semillas y se procedió a la identificación y cuantificación fitoquímica. Los linfocitos humanos purificados se expusieron a 12,5; 25; 50 μg/mL de extracto de Momordica charantia durante 24 horas y después de este período. Resultados : Los datos mostraron que el extracto de Momordica charantia no indujo citotoxicidad, alteraciones en la frecuencia de micronúcleos, ni actividad de interleucina-6, interleucina-10 ciclooxigenasa-2 y producción de óxido nítrico; sin embargo, causó daño en el ADN y una disminución de TNF-α en las condiciones experimentales y células aplicadas. Conclusiones : Nuestros datos proponen un proceso antiinflamatorio generado por Momordica charantia mediado por la reducción de TNF-α. (AU)


Introduction: Momordica charantia L. is widely used for consumption and traditional medicine due to its biolog-ical activities. Nevertheless, little is known about the effects of bitter melon on healthy cells. Hence, we aimed to evaluate the effects of Momordica charantia extract in human isolated lymphocytes, especially on inflammatory, cytotoxicity, genotoxicity, and mutagenicity aspects. Method: For this, we prepared a hydroethanolic extract with fruits and seeds and proceeded with phytochemical identification and quantification. The human purified lymphocytes were exposed to 12.5, 25, and 50 μg/mL of Mo-mordica charantia extract for 24h and, after this period. Results: The data showed that the Momordica charantia extract did not induce cytotoxicity, micronucleus frequen-cy alterations, or interleukin-6, interleukin-10 cyclooxygenase-2 activity and the production of nitric oxide; however, it caused DNA damage and a decrease of TNF-α under the experimental conditions and cells applied. Conclusions: Our data propose an anti-inflammatory process generated by Momordica charantia mediated by TNF-α reduction. (AU)


Assuntos
Humanos , Momordica charantia/efeitos adversos , Linfócitos , Fator de Necrose Tumoral alfa , Frutas , Extratos Vegetais , Interleucinas
6.
J Ethnopharmacol ; 287: 114956, 2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-34965457

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Sida tuberculata R. E. Fries (Malvaceae) is a pioneer species considered a weed in farm fields in Southern Brazil. Widely distributed in South Brazil, S. tuberculata is popularly used to treat inflammatory conditions. AIMS OF THE STUDY: The current study aimed to assess the in vitro cytotoxic and in vivo anti-inflammatory properties of S. tuberculata. MATERIALS AND METHODS: Initially, extracts obtained from leaves (STLE) and roots (STRE) were submitted to cytotoxicity tests using human leukocytes (non-malignant cell line) and HepG2 and MCF-7 (tumor cell lines). In sequence, anti-inflammatory properties were investigated against carrageenan-induced peritonitis model. RESULTS: In vitro analyses displayed a significant decrease in human leukocytes viability without genotoxic damage. IC50 results from tumor cells presented significant decrease in cell viability, slightly more pronounced for STRE. In addition, STLE significantly inhibited the inflammatory and oxidative parameters (TBARS, NPSH, SOD, MPO activity, cell influx, and cytokines release). CONCLUSION: Our findings indicate S. tuberculata extracts have cytotoxic potential more pronounced on tumor cell lines, as well as leaves extract shows a significant reduction in acute inflammation process, as already reported for Sida genus and specifically for this species.


Assuntos
Anti-Inflamatórios/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Extratos Vegetais/farmacologia , Sida (Planta)/química , Animais , Anti-Inflamatórios/isolamento & purificação , Antineoplásicos Fitogênicos/isolamento & purificação , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Carcinoma Hepatocelular/tratamento farmacológico , Linhagem Celular , Modelos Animais de Doenças , Feminino , Células Hep G2 , Humanos , Inflamação/tratamento farmacológico , Inflamação/patologia , Neoplasias Hepáticas/tratamento farmacológico , Células MCF-7 , Masculino , Camundongos , Peritonite/tratamento farmacológico , Peritonite/patologia
7.
Braz. J. Pharm. Sci. (Online) ; 58: e20096, 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1403677

RESUMO

Abstract Dexchlorpheniramine is a first-generation classical antihistamine, clinically used to treat allergies. The main objective of our study was to evaluate the effects of the dexchlorpheniramine reference standard (DCPA Ref. St) and a pharmaceutical formula on DNA in human peripheral blood mononuclear cells (PBMCs). We exposed PBMCs to five different concentrations (0.5, 2.5, 5, 10, and 50 ng/mL) of DCPA Ref. St DCPA Ref. St and pharmaceutical formula in order to evaluate their cytotoxic, genotoxic, and mutagenic potential. The results showed that both dexchlorpheniramine formulations did not affect PBMC viability and CD3+, CD4+, or CD8+ lymphocyte subpopulations. The DCPA Ref. St and pharmaceutical formula neither induced genotoxic or mutagenic effects nor numerical or structural chromosomal alterations in PBMCs after 24 hours of exposure.


Assuntos
Humanos , Leucócitos Mononucleares/metabolismo , Citotoxicidade Imunológica , Composição de Medicamentos , Genotoxicidade , Testes de Mutagenicidade , DNA/análise , Antagonistas dos Receptores Histamínicos/efeitos adversos , Hipersensibilidade/complicações
8.
Braz. J. Pharm. Sci. (Online) ; 58: e19491, 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1383957

RESUMO

Abstract The illicit market of counterfeit medicines containing sildenafil and tadalafil has been causing serious public health problems. Thus, further studies on this illicit association are needed. A stability-indicating HPLC method was developed for simultaneous determination of tadalafil (TAD) and sildenafil (SIL) using a C18 column (250 x 4.6 mm, 5 µm). Detection was achieved at 284 nm, for TAD, and 292 nm, for SIL. The method was considered to be specific, linear, precise, accurate, robust, and sensitive. In the photodegradation kinetic studies, the drugs showed a first-order reaction rate when isolated, and zero-order when associated. Toxicological assays demonstrated that the photodegraded drugs decreased cell viability in compared to non- degraded drugs, suggesting cytotoxic activity. Additional, mutagenic activity was not observed under the tested conditions. Photodegraded drugs, in association, depicted DNA damage index, suggesting genotoxic effects. The obtained results will be able to support the forensic intelligence laboratories, as well as to alert the population about the risk inherent to consuming counterfeit products.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Fotodegradação/efeitos dos fármacos , Citrato de Sildenafila/análise , Tadalafila/análise , Medicamentos Falsificados/classificação
9.
J Med Food ; 24(6): 660-665, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33179973

RESUMO

Yacon is an Andean plant that has been used in folk medicine for its medicinal properties. The beneficial effects of this plant are possibly due to the high content of phenolic compounds present in its leaves and roots. This study evaluated the in vitro toxicity of the hydroalcoholic extract of leaves and roots from yacon (1, 10, 50, and 100 µg/mL) through cell viability tests, genotoxic and mutagenic activity in leukocytes culture cells; and cytotoxicity and apoptosis cell death (1, 10, 50, 100, and 500 µg/mL) in cell line originally established from the primary mouse embryonic fibroblast cells that were cultured by the designated protocol, so-called 3T3 protocol "3-day transfer, inoculum 3 × 105 cells" (3T3 cell line). No mutagenic and cytotoxic activities were observed in leukocyte cultures. Cytotoxic activity was evidenced in the highest concentrations of yacon leaf extract (50 and 100 µg/mL), whereas all concentrations tested with yacon leaf extract there was induction for apoptosis in the 3T3 cells. Genotoxic potential was observed only at higher doses of leaf (50 and 100 µg/mL) and root (100 µg/mL) extract. These results suggest that yacon leaf at high concentrations may present toxic potential showing concentration-dependent behavior; however, in vivo studies should be performed to validate these results.


Assuntos
Asteraceae , Extratos Vegetais , Animais , Sobrevivência Celular , Fibroblastos , Camundongos , Fenóis/toxicidade , Extratos Vegetais/toxicidade , Folhas de Planta
10.
Artigo em Inglês | LILACS | ID: biblio-1349461

RESUMO

Objective: the development of new drugs against Methicillin-resistant Staphylococcus aureus is a priority to the World Health Organization. So, the objective of this study was to evaluate the antibacterial activity and toxicity of 5-bromo-3-((4-methoxyphenyl) sulfenyl)-1H-indole (3b) against MRSA. Methods: minimum inhibitory concentration (MIC) of 3b was determined against S. aureus ATCC 29213 and 43 clinical isolates. The time-kill assay was performed for 9 isolates. Analysis of variance followed by the post hoc Bonferroni test was used for the statistical tests. Results and conclusions: the MIC50 and MIC90 of 3b were 4 µg.mL-1 and 16 µg.mL-1 respectively. In time-kill assay, the 3b showed bactericidal activity to all evaluated isolates at concentrations of 1xMIC and 2xMIC and the re-growth effect was not observed. About the toxicity tests, 3b has not presented cytotoxicity, mutagenicity, or allergenicity. 3b had particularly good activity against MRSA demonstrating high potential for the development of new antimicrobials products.


Objetivo: o desenvolvimento de novos antimicrobianos contra Staphylococcus aureus resistentes à meticilina (MRSA) é uma prioridade para a Organização Mundial da Saúde. Então, o objetivo desse estudo foi avaliar a atividade antibacteriana e a toxicidade do 5-bromo-3-((4-metoxifenil) sulfenil)-1H-indol (3b) contra MRSA. Métodos: a concentração inibitória minima de 3b foi determinada contra S. aureus ATCC 29213 e 43 isolados clínicos. O ensaio de curva de morte foi realizado para nove isolados. Análise de variância seguida pelo teste post hoc Bonferroni foi usada para testes estatísticos. Resultados e conclusões: a MIC50 e MIC90 do 3b foi 4 µg.mL-1 e 16 µg.mL-1, respectivamente. No ensaio de curva de morte, o 3b demonstrou atividade bactericida contra todos os isolados avaliados na concentração de 1xMIC e 2xMIC e o recrescimento não foi observado. Em relação aos testes de toxicidade, 3b não apresentou citotoxicidade, mutagenicidade ou alergenicidade. 3b apresentou atividade particularmente interessante contra MRSA, demonstrando alto potencial para o desenvolvimento de novos produtos antimicrobianos.


Assuntos
Staphylococcus aureus , Staphylococcus aureus Resistente à Meticilina , Resistência a Meticilina , Anti-Infecciosos , Antibacterianos
11.
Immunopharmacol Immunotoxicol ; 42(5): 504-508, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32811239

RESUMO

AIM: Steviol is a natural diterpenoid glycoside isolated from Stevia rebaudiana Bertoni leaves and widely used as a non-caloric sweetener. In addition to their sweet taste, Steviol glycosides may also have some therapeutic benefits. There are few reports on the cytotoxicity of Steviol in human cells. Our objective was to test this sweetener under and at average concentrations of consumption, evaluating parameters of cytotoxicity, genotoxicity, and immunotoxicity. METHODS: For this purpose, we made use of lymphocyte cultures and the analysis of their CD3+, CD4+, and CD8+ subpopulations. In a complementary way, the mechanism of action is proposed here by computational methods. RESULTS AND CONCLUSION: Our results showed that Steviol reduces the number of lymphocytes due to falls of CD4+, CD8+, and CD4+CD8+ subpopulations. Besides, we observed an increase in the level of DNA damage and a gradual incidence of structural changes in the lymphocyte chromosomal sets. It was possible to propose that Steviol modulates gene expression, mainly interfering with the SESN1, NAP1L1, SOX4, and TREX1 genes. Although Steviol is used globally as a sweetener, its use should be cautious, as our study points out that Steviol has cytotoxic, genotoxic and mutagenic effects in the concentrations and conditions tested in the culture of human lymphocyte cells.


Assuntos
Dano ao DNA , Diterpenos do Tipo Caurano/toxicidade , Subpopulações de Linfócitos/efeitos dos fármacos , Edulcorantes/toxicidade , Células Cultivadas , Relação Dose-Resposta a Droga , Exodesoxirribonucleases/genética , Exodesoxirribonucleases/metabolismo , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Humanos , Subpopulações de Linfócitos/metabolismo , Subpopulações de Linfócitos/patologia , Proteína 1 de Modelagem do Nucleossomo/genética , Proteína 1 de Modelagem do Nucleossomo/metabolismo , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Medição de Risco , Fatores de Transcrição SOXC/genética , Fatores de Transcrição SOXC/metabolismo , Testes de Toxicidade
12.
Clin Exp Pharmacol Physiol ; 47(10): 1751-1757, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32542867

RESUMO

One of the most widely used sweeteners in the world is sucralose. With sweetening power 600 times greater than sucrose, its use grows among those who seek to cut calories. Research shows that when heated, sucralose generates toxic products that attack the organism and interact with DNA. Our objective was to test this sweetener under unheated conditions and at average concentrations of consumption, evaluating parameters of cytotoxicity, genotoxicity, and immunotoxicity. For this purpose, we made use of lymphocyte cultures and the analysis of their CD3+ , CD4+ , and CD8+ subpopulations. In a complementary way, the mechanism of action is proposed here by computational methods. Our results showed that sucralose reduces non-selectively the total lymphocytes due to falls in the levels of the CD4+ , CD8+ , and CD4+ CD8+ subpopulations. We observed an increase in the level of DNA damage and a gradual incidence of structural changes in the lymphocyte chromosomal sets. It was possible to propose that sucralose modulates the gene expression, interfering especially with the MAPK8, APTX, and EID1 genes. This article presents the results of an evidence-based approach to the safety of human health in the use of sucralose. Finally, this study points out that sucralose has cytotoxic, genotoxic, and mutagenic effects in the concentrations and conditions tested in human lymphocyte cell culture.


Assuntos
Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/efeitos dos fármacos , Simulação por Computador , Sacarose/efeitos adversos , Edulcorantes/efeitos adversos , Ingestão de Energia/efeitos dos fármacos , Humanos
13.
Toxicon ; 182: 7-12, 2020 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-32376361

RESUMO

Fumonisin B1 is a mycotoxin produced by Fusarium verticillioides and Fusarium proliferatum found in various crops, particularly maize. Besides carcinogenicity, other manifestations have been registered in different animals and in humans. In the case of humans, epidemiological studies have reported high prevalence of esophageal cancer in populations exposed to fumonisins. This study aimed to evaluate the minimum concentration of FB1 capable of inducing cytotoxicity (cell viability test), genotoxicity (comet assay) and mutagenicity (micronucleus) in cultured human leukocytes and to evaluate the effectiveness of in silico tests to predict FB1 toxicity. All concentrations analyzed (200; 100; 50; 5; 0.5; 0.05; 0.005 µg/mL and 300; 30; 3; 1; 0.1; 0.01 fg/mL) except the lowest demonstrated dose-dependent toxicity in all parameters analyzed (p < 0.05 to p < 0.0001). As for predictions, only the Lazar software showed carcinogenicity of FB1 for rats. Thus, it is evident that FB1 is able to induce dose-dependent damage at low concentrations, and that computational tests, although desirable for prediction, are not effective as biological tests to determine toxicity, at least of FB 1 and within the experimental conditions tested.


Assuntos
Carcinógenos Ambientais/toxicidade , Fumonisinas/toxicidade , Contenção de Riscos Biológicos , Humanos
14.
Braz. J. Pharm. Sci. (Online) ; 56: e18355, 2020. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1089168

RESUMO

Danofloxacin is a veterinary fluoroquinolone used to treat respiratory and gastrointestinal diseases of birds, pigs and cattle. The literature reviewed shows some analytical methods to quantify this fluoroquinolone, but microbiological and biological safety studies are limited. The analytical methods were validated by the Official Codes. The LC-DAD method was developed and validated using an RP-18 column, mobile phase containing a mixture of 0.3% triethylamine (pH 3.0) and acetonitrile (85:15, v/v). The microbiological assay was performed by agar diffusion method (3 x 3) and Staphylococcus epidermidis as a microorganism test. Forced degradation studies were performed in both methods. The minimum inhibitory concentration (MIC) was performed by test microdilution and toxicity studies were evaluated using in silico study, cell proliferation, cell viability test, micronuclei and comet assay. LC and a microbiological assay proved linear, accurate, precise, and robust to quantify danofloxacin, but only the LC method showed selectivity to quantify the drug in the presence of its degradation products. These results demonstrate that the LC method is suitable for stability studies of danofloxacin, but a microbiological assay cannot be used to quantify the drug due to the biological activity of the photoproducts. Ex-vivo cytotoxicity and theoretical and experimental genotoxicity were also observed.

15.
Saudi Pharm J ; 27(8): 1064-1074, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31885466

RESUMO

Development of new antimicrobial agents, capable of combating resistant and multidrug-resistant fungal and bacterial clinical strains, is necessary. This study presents the synthesis and antimicrobial screening of 42 2-substituted-1,4-benzenediols, being 10 novel compounds. In total, 23 compounds showed activity against fungi and/or bacteria. Benzenediol compounds 2, 5, 6, 8, 11, and 12 demonstrated broad spectrum antimicrobial actions, including resistant and multidrug-resistant species of dermatophytes (Trichophyton mentagrophytes), Candida spp. and the ESKAPE panel of bacteria. Minimum inhibitory concentrations of these compounds for fungi and bacterial strains ranged from 25 to 50 µg/ml and 8-128 µg/ml, respectively. The antifungal mechanism of action is related to the fungal cell wall of dermatophytes and membrane disruption to dermatophytes and yeasts, in the presence of compound 8. Specific structural changes, such as widespread thinning along the hyphae and yeast lysis, were observed by scanning electron microscopy. The effects of compound 8 on cell viability are dose-dependent; however they did not cause genotoxicity and mutagenicity in human leukocyte cells nor haemolysis. Moreover, the compounds were identified as nonirritant by the ex-vivo Hen's egg test-chorioallantoic membrane (HET-CAM). The furan-1,4-benzenediol compound 5 showed in vivo efficacy to combat S. aureus infection using embryonated chicken eggs. Therefore, the compounds 8, and 5 are promising as hits for the development of new antimicrobial drugs with reduced toxicity.

16.
Artigo em Inglês | MEDLINE | ID: mdl-31205477

RESUMO

Fluazuron is one of the newest veterinary antitick medicines. Belonging to the benzoylphenylureas group, its mechanism of action acts by the interference of the formation of the chitin of the tick, which is responsible for the hardening of its exoskeletons. In addition to taking care of the health of the animal so that it receives the medication in the doses and the correct form, it is important to analyze the safety of the operator. Reduced resistance to infectious disease was a well-documented consequence of primary and acquired immunodeficiencies, but a novel finding following xenobiotic exposure. The awareness of the consequences of altered immune function is the most likely outcome of inadvertent exposure. The human health implications of studies in which chemical exposure reduced resistance to infection drove an early focus on immunosuppression within the toxicology community. The main objective is to perform the evaluation by computational platforms and in cell culture, searching for data that can serve as a foundation for a better understanding of the toxic effects involved with the accidental contamination of Fluazuron and, thus, to assist the medical community and users to understand the risks inherent in its use. As far as we can determine in the literature, our work has unmistakably demonstrated that the Fluazuron can cause genotoxicity by probable chromatin rearrangement and immunodepleting by specific reduction of the CD8 T lymphocyte subpopulation, mediated by the decrease in gamma interferon production. Although the use of Fluazuron is a necessity for tick control and for cattle management, we must bear in mind that the imminent risks to its application exist. Careless use can damage the immune system which in turn carries a gigantic hazard by opening a door to diseases and pathogens and leaving us defenseless.

17.
J Anal Methods Chem ; 2019: 7534609, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30944754

RESUMO

A stability-indicating LC method was developed for quantification of linagliptin (LGT) and three synthetic impurities. The method utilizes a Thermo Scientific® RP-8 column (100 mm × 4.6 mm; 5 µm) with the PDA detector for quantitation of impurities. A mixture of 0.1% formic acid with pH 3.5 (A) and acetonitrile (B) was used as the mobile phase at a flow rate of 0.6 mL·min-1 with gradient elution. The percentage of mobile phase B increases from 30% to 70% over 5 min and decreases from 70% to 30% between 5 and 8 min. The method was validated according to International Council for Harmonization (ICH) guidelines. The LOD values obtained were 0.0171 µg·mL-1 and 0.015 µg·mL-1 for LGT and impurities, respectively. The LOQ values were 0.06 µg·mL-1 for LGT and impurities. In all cases, the correlation coefficients of LGT and impurities were >0.999, showing the linearity of the method. The % recovery of the LGT and added impurity were in the range of 92.92-99.79%. The precision of the method showed values less than 1.47% for LGT and less than 4.63% for impurities. The robustness was also demonstrated by small modifications in the chromatographic conditions. The selectivity was evidenced because the degradation products formed in stress conditions did not interfere in the determination of LGT and impurities. Toxicity prediction studies suggested toxicity potential of the impurities, which was confirmed using biological safety studies in vitro.

18.
Sci Total Environ ; 675: 343-353, 2019 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-31030141

RESUMO

This study evaluated the Limnoperna fortunei (golden mussel) as a bioindicator of cytotoxicity and genotoxicity in aquatic environments contaminated by heavy metals. Five groups of 50 subjects each were exposed to different concentration of mercuric chloride (HgCl2) (0.001 mg/L, group I; 0.005 mg/L, group II; 0.01 mg/L, group II; 0.02 mg/L, group IV; and 0.1 mg/L, group V). The control group for both chronic and acute treatment did not receive HgCl2. For chronic exposure, the respective groups were placed in aquaria with water contaminated with the above concentrations of HgCl2. For acute exposure, the different concentrations of HgCl2 were injected into the posterior adductor muscle of the individuals belonging to the aforementioned groups. The biological matrix used in the tests was the whole body muscle. Tests (cell viability assay, alkaline comet test; enumeration of micronuclei and necrotic cells, quantification of Hg content in tissues and water, and histopathological analysis of tissues), were carried out on the 7th, 15th, and 30th treatment days or 2 h after injection. Our results demonstrated that L. fortunei showed cell damage in both chronic and acute exposure groups. Significant DNA damage was observed at both the 15th (0.1 mg/L) and 30th (0.01-0.1 mg/L) days of chronic exposure. However, in acute treatment all concentrations induced DNA breaks. The presence of necrosis increased at all concentrations tested for both acute and chronic exposure. Tissue mercury retention on the 15th day was higher than on the 30th day of exposure, while in the same period, there was a decrease in the mercury content of aquarium water. Taking the data together, it is concluded that L. fortunei as a possible bioindicator of the quality of aquatic environments.


Assuntos
Monitoramento Ambiental , Mercúrio/toxicidade , Mytilidae/fisiologia , Poluentes Químicos da Água/toxicidade , Animais , Dano ao DNA , Biomarcadores Ambientais
19.
Rev. colomb. ciencias quim. farm ; 48(1): 145-158, jan.-abr. 2019. graf
Artigo em Inglês | LILACS | ID: biblio-1042804

RESUMO

SUMMARY Cadmium (Cd2+) is a nonessential heavy metal that possesses a high capacity of bioaccumulation and exhibits toxic characteristics even at low concentrations. This study evaluated the genotoxicity and cytotoxicity in human leukocytes in vitro after exposure to a lower range of Cd2+concentration (1-25 (g/mL) using an unprecedented strategy by correlating between intracellular Cd2+ levels after exposure and cellular damage. Results demonstrated that Cd2+exposure from 5 to 25 fig/mL significantly increased the unviability of leukocytes, as well as the DNA damage, which was dose-dependent. The intracellular Cd2+ levels in leukocytes ranged from 9.85 to 94.38 pg/cell, and cytotoxicity and genotoxicity were induced at a concentration of24.22 pg/cell. The relationship between exposure concentration and intra-cellular Cd2+ levels suggests that its influx occurs in human leukocytes under zero-order kinetics.


RESUMEN El cadmio (Cd2+) es un metal pesado no esencial que posee una alta capacidad de bioacumulación y presenta características tóxicas incluso en bajas concentraciones. Este estudio evaluó la genotoxicidad y la citotoxicidad en leucocitos humanos in vitro después de la exposición a un rango inferior de concentración de Cd2+ (1-25 (g / mL) mediante una estrategia sin precedentes al correlacionar los niveles intracelulares de Cd2+ después de la exposición y el daño celular. Los resultados demostraron que la exposición a Cd2+ de 5 a 25 (g/mL aumentó significativamente la inviabilidad de los leucocitos, así como el daño en el ADN, que era dependiente de la dosis. Los niveles intracelulares de Cd2+ en leucocitos oscilaron entre 9,85 y 94,38 pg/célula, y se indujo la citotoxicidad y la genotoxicidad a una concentración de 24,22 pg/ célula. La relación entre la concentración de la exposición y los niveles intracelulares de Cd2+ sugiere que su influjo se produce en leucocitos humanos bajo una cinética de orden cero.

20.
Acta sci., Biol. sci ; 41: e45014, 20190000. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1460848

RESUMO

The steroid hormones are lipids in nature, which play crucial roles in several metabolic and behavioral pathways in mammals. Drug therapy uses sterol hormones for treating some disturbances linked with its deficiency; however, the illicit use of these hormones by amateur and elite athletes to enhance performance or body appearance may lead to several health issues. In this study we evaluated the anxious-like behavior and the long-term memory acquisition of male rats undergoing sedentary life-style or physical effort, with or without anabolic-androgenic steroids (ASC) treatment. The results showed a decrease in anxious-like behavioral levels in rats that received ASC treatment associated or not with physical effort, but this treatment did not affect the acquisition of long-term memory at the dose and experimental model assessed.


Assuntos
Animais , Ratos , Ansiedade , Congêneres da Testosterona/administração & dosagem , Ratos/anormalidades
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